Internal-combustion engine



J. 0. W. LAVALLEE. INTERNAL 00MBusloNl-EnmINEl APPLICATION FILED MSHA I4, 1920.

Patented Dec. 5, 1 922.

Patente-d Een. 5, i922.

narra a JOSEPH O. W. LAVALLEE, 0F MONTREAL, QUEBEC, CANADA, ASSIGNOR TO CARON BROTHERS, 0F MONTREAL, CANADA.

INTERNAL-COMBUSTION ENGINE.

Application filed April 14, 1920. Serial No. 373,906.

To all whom t may concern:

Be it known that l, JosnPi-r Osoon WIL- luucn Lxvnnnnn, a subject ofthe King of yGreat Britain and ireland7 residing at the city of Montreal, Dominion of Canada, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention relates to improvements in an internal combustion engine of the twocycle type and more particularly to an engine in which the fuel mixture undergoes primary compression inside the piston and it has for its object to provide an engine of simple and cheap construction that will develop a high power efficiency and economical operation.

A further object of this invention is to provide means to preheat the fuel mixture during the primary compression.

Another object of this invention is to provide a novel means of compressing the fue] mixture within the piston. p

Reference is made to the annexed drawings in which Fig. 1. shows a vertical cross section through the axis of the crank, with the piston at the top of its stroke.

Fig. 2. a vertical cross section at right angles to that of Fig. 1. through the axis of the cylinder with the piston inthe same position.

Fig. 3. the same cross section as Fig. 1. but with the piston at the bottom of its stroke.

Fig. 11. the same cross section as Fig. 2. but with the piston as in Fig. 3.

rThe engine is preferably supported by a crank case consisting of a base 1 and cover 2. The cylinder 3 is secured to the top of the crank case by the flanges 4 and suitable bolts or screws. rlhe upper portion of the cylinder 3 is water jacketed at 5. The cylinder head 13 with. Water jacket 14., is secured to the cylinder by stud bolts 18, (i is the water" inlet and 15 the water outlet. in the walls of the cylinder 3, are the exhaust port 7 the fuel feed port 8 and the bypass 10, which extends between the ports 11 and 12.

rl`he cylindrical piston 19 is slidably mounted in the cylinder 3, and is cast integral with the central transverse sleeve 30 in which the wrist pin 20 is journalled. Thls wrist pin 2O projects through vertical slots 21 in they opposite sides of the cylinder.

Connecting rods 22 are secured to the projecting ends of the wrist pin and are connected by the sleeve 27 over the crank 24. of the crank shaft 25. Suitable bearings 26 in the crank case 1 and 2 support the shaft 25. The connecting rods 22 pass through slots 23 in the cover 2.

An inverted lianged cup shaped plug 31 is screwed into the top of the cover 2 and is adapted to enter the lower open end of the piston 19. This plug 31 may be adjustable as to size and length.

The piston head is provided with the usual baflie 33 to d'eiect the mixture from the exhaust port.

ln the cylinder head 13 are the spark plug 16 and priming pet-cock 17.

The operation of the invention is as follows- When the piston is at the top of its stroke as appears in Figs. 1 and 2, a charge of compressed mixture is in the cylinder head ready to be exploded by the spark from the spark plug.

The feed port 8 is open and a fresh charge of mixture fills the whole of the ini terior of the piston, the by-pass 10 is closed at its upper port 12 by the piston Wall.

After the explosion as the piston begins to descend the port 8 is closed and the plug 31 enters the lower end of the piston and compresses the mixture therein and heats it by the heat of the piston head.y

When the piston has reached the bottom of its stroke as shown in Figs. 3 and 4. The exhaust port 7 is opened and the'exhaust gases pass out at the same time the by-pass port 12 opens and the heated compressed mixture passes around the plug 31 through the port 11 into the by-pass 10 and thence through the port 12 where it meets the baffle 33 and fills the cylinder above the piston. Ou the return stroke of the piston the exhaust port 7 and by-pass port 1.2 are closed and mixture in the cylinder is compressed still further. As the piston is drawn up from around the plug a partial vacuum is produced in the piston so that when the feed port 8 is again opened a fresh charge is rapidly sucked in and fills the piston.

By means of this construction it is found that the fresh charge of mixture cools the piston head, and absorbs heat from it, thereby becoming preheated.

That its passage around the plug and through the by-pass to the cylinder keeps it thoroughly mixed.

That the long by-pass and cooled piston head prevents back fire. That the preheated :mixture when subjected to secondary compression develops increased eiciency and economy.

Having now described my invention what l claim is:

l. In an engine of the class specified, the combination of a cylinder closed at both ends, and with slotted walls, with a cylindrical piston with one end open and centrally journalled to a transverse wrist pin which projects through the cylinder slots, a crank shaft, connecting rods coupled to wrist pin and crank of crank shaft, and a plug projecting inwardly from cylinder end and adapted to enter open end of piston.

2. ln an engine of the class specified, the combination of a centrally j ournalled cylindrical piston, having one end open, with a cylinder having slotted walls and an end forming an inwardly extending plug, adapted to enter the open end of the piston, without contacting therewith.

3. ln an engine of the class specied'the co-mbination of a centrally journalled cylindrical piston, having one end open, with a cylinder having slotted walls, and a removable end forming an inwardly extending plug, adapted to enter the open end ot the piston, without contacting therewith.

t. ln an engine of the class specified the combinationoi' a centrally ournalled cylindrical piston, having one end open, with a cylinder having slotted walls,` and an end of variable length, forming an inwardly extending plug, adapted to enter the open end of the piston, without contacting therewith.

5. ln a gas engine of the type specified, the combination oi a single cylinder having an inwardly projecting plug at one end and central vertical slots in the walls, a hollow piston closed at one end and having a central transverse sleeve, mounted in the said cylinder, a wrist pin journalled in said sleeve, and projecting through said slots, the interior of said piston forming with the walls and plug of cylinder a compression chamber.

6. In a gas engine of the type specified, the combination of a single cylinder, a hollow piston centrally journalled to connecting rods through slots in the cylinder walls and a cup shaped plug forming one end of the cylinder and projecting inwardly, adapted to enter open end of the piston and iorm therewith a compression chamber.

7. In a gas engine, the combination of a crank case, a single cylinder supported thereon, having an explosive chamber at its .upper end and a removable inwardly projecting plug at its lower end, a hollow piston. mounted in said cylinder with the upper end closed and the lower end open, said cylinder being provided with vertical slots cen trally arranged in its walls, a wrist pin centrally journalled in said piston, connecting rods outside the cylinder and a crank shaft coupled to the ends of wrist pin by said connecting rods.

8. In a gas engine of the type specified, the combination of a single cylinder supported on a crank case, t-he upper end torming an explosion chamber, a cup shaped plug projecting inwardly forming the lower end of the cylinder, central-vertical slots in the walls of the cylinder, a hollow cylindrical piston having the upper end closed and a central transverse sleeve, mounted in said cylinder, the interior of the piston and the inwardly projecting plug and cylinder walls `forming a compression chamber, a wrist pin journalled in thetransverse sleeve of the piston and projecting through the slots ofthe cylinder walls, a crank sleeve integral with two connecting rods which are secured to the ends of the wrist pin and a crank shaft on which the crank sleeve is journalled.

Signed at Montreal this eighth day of April i920.

J. o. W. LAVALLEE. 

